text: # -*- coding: utf-8 -*-
  # @Time    : 2020/10/8 09:47
  # @Author  : ooooo
  
  from typing import *
  
  
  class Solution:
      def reverseString(self, s: List[str]) -> None:
          for i in range(len(s) // 2):
              s[i], s[-i - 1] = s[-i - 1], s[i]
  